带压开采陷落柱突水影响因素数值模拟  

Numerical simulation for the influential factors of water inrush of karst collapse column in the process of mining above the aquifer

作　　者：李振华[1] 翟常治 李龙飞[1] 

机构地区：[1]河南理工大学能源科学与工程学院,河南焦作454010

出　　处：《安全与环境学报》2015年第4期41-46,共6页Journal of Safety and Environment

基　　金：国家自然科学基金项目(51374093;51104058);教育部高等学校博士学科点专项科研基金项目(20114116120005)

摘　　要：为研究承压水压与煤层陷落柱位置这两种因素对陷落柱突水的影响,在分析固流耦合数学模型的基础上,利用数值模拟软件FLAC3D,以双柳矿地质条件为背景,分别对3 MPa和5 MPa承压水压下开采上、下两组煤4种情况进行模拟,分析陷落柱及其周边围岩的渗流-塑性破坏耦合场、应力场和位移场的变化。结果表明：随着工作面推进至接近陷落柱,工作面前方集中应力场与柱体周边应力场发生耦合,并出现应力集中,当水压为5 MPa开采上组煤时应力集中系数最大,最容易形成突水危险区域;当上组煤工作面距离陷落柱为30m时,陷落柱渗流场与集中应力场开始连通,在开采下组煤时这一距离比上组煤扩大15~20 m;煤层底板随工作面推进发生压缩-膨胀周期变化,引起拉伸、剪切破坏。The paper intends to make a numerical simulation for the influential factors of water inrush of karst columns prone to collapse in the process of mining above the aquifer in hoping to analyze the failure pattern of the collapse columns and the mechanism of the water inrush. The whole simulation is done based onthe study of the water inrush mechanism from the point of view of coal seam in the mine above the confined aquifer by taking the geological conditions of Shuangliu mine as a research sample. In this paper,we have also analyzed the evolution or the change of the stress,strain and the plastic section of the likely-to-be-collapsed columns and their surrounding rocks while performing our simulation with the collapse columns via a software FLAC3 Dwhen the upper and lower coal seams were mined under different water pressures. The results of our simulated research show that the stress,the displacement and the seepage files of the surrounding rock mass are not likely to affect each other when the working faces keep away from the said column. However,the stress concentration tends to occur with the working face being pushed close to the collapse column while the coupling behavior takes place between the stress-concentrating fields in the front part of the goaf and the surrounding stress field of the column. In that case,when the upper coal seam is mined under the water pressure of 5 MPa,the stress concentration factor would become the biggest and the risk of the water inrush area is likely to come about. In so doing,the distance between the goaf of the upper coal seam and the collapse column may get close to 30 m,with the seepage turning to be involved with the concentrated stress. When the lower coal seam is mined,the distance would extend to 15- 20 m. With the working face being squeezed and pushed away,the stress in the coal floor is likely to suffer a periodic change,leading to the tensile failure,shear failure of the coal floor and the fracture redistribution of the collapse column,and eventually resulting in t

关 键 词：安全工程 带压开采 岩溶陷落柱 突水影响因素 数值模拟 

分 类 号：X752[环境科学与工程—环境工程]